Sound of Silence
by shadowoah
Summary: Cas is tricked into working for a supernatural creature unknown to anyone, because someone is hunting them, and they chose him to do the work that they cannot. In his work, he must go behind Sam and Dean in order to save them. The clock is ticking. Will Cas crack under pressure? Will he save the Winchesters, or will he die trying?
1. Chapter 1

The stars were especially bright tonight, Castiel noticed. He vaguely wondered if the other angels even bothered to notice the beauty of the earth, instead of hating it for catching them in their fall, in the end deciding that they probably didn't care one bit.

It was quiet too, a sound he appreciated. It could be compared to a human's need for sleep. Sometimes, an angel could really use a few hours of silence, to clear his thoughts and ease his soul. He opened his arms a little and turned to face away from the road, watching the wheat fields, stretching as far as he could see, swaying gently in the warm night breeze.

He took it all in. The night, the open space, the crops, the absoluteness of it all. Totally relaxed, he closed his eyes. Everything was okay, for once. Sam and Dean were asleep in the Impala, Cas having convinced them to sleep out in the open for a change. They were in between hunting jobs, but with Cas' powers being stronger than before, it was almost enjoyable.

But of course, nothing in his life ever stayed good long. It happened so quickly, Cas almost thought he had imagined it in his relaxed state of mind. Then it appeared again. And again. He blinked, and looked back at the car. There was no sign of danger.

Cautiously turning back around, he allowed his eyes to flutter shut, trying to seep back in to the comforting starlight. For a moment, nothing else happened. Then he dropped to the ground, clutching his head, and squeezing his eyes shut.

He saw images flashing by. A pair of apple green eyes. Little white flurries swirling downwards. A massive raven feather, contrasted vividly by pure white. The pictures began blurring together, and finally eased into a continuous stream in which he could clearly make out a hill covered in thick snow, with flakes still steadily tumbling down.

Confused, he attempted to move in this vision-scape and was surprised to be able to. He took in his surroundings. Nothing but snow. It was unnerving, to see an entire landscape white. Even the sky was a pale grey. This silence was anything but comforting. He felt trapped, frozen in place by some intensely strong force.

Jerking him out of his musing was a burst of movement spotted out of the corner of his hawk-like eyes, on the edge of a forest. His ghostly form glided to this new observance, but stopped a few yards from the closest tree. At his feet, was a messy stain of red. _Blood_. Even more puzzled than before, he stooped down to get a better look. Just as he was about to reach out and touch it, a snowflake floated into his eye and he blinked to clear his vision.

And once more, he was staring back at the stars in the wheat fields. Rattled, his first gut reaction was to tell Sam and Dean. Yet something told him that he shouldn't. At least, not yet. He just got Sam's soulless problem fixed and Dean's trust back, and didn't want to worry them more with some weird vision he had one time. It probably was nothing. If it was something, he would fix it himself.

Just when he thought things couldn't get any stranger, he noticed a weight on his back, and the light of the stars gave off a larger shadow behind him than before.

 _No._ He hissed to himself, not wanting to believe what he knew had somehow happened. _It is impossible._

Without making any noise, he walked back to the Impala and peered at himself in a side mirror. His turquoise orbs were scrunched up in worry and he gasped when he saw them.

In awe, he flapped the appendages sprouting from between his shoulder blades. Pearly black and powerfully extended, he could only think of how much he missed them, and how much they had healed from flying through Hell. Suddenly, he felt a tinge of panic. What if the Winchesters woke up and saw his…wings? They were not meant for a human to see. His mind began to race in worry, but as he stepped away from the mirror, something changed.

As quickly as they had come, they disappeared, invisible once again. Castiel suddenly had an urge to run away, to get somewhere even remoter than the little patch of dirt on the side of an old country road. He checked on the undisturbed sleeping forms of the Winchesters once more, then vanished with a gentle whoosh.

He appeared in the middle of a field, close to the boys, but far enough away so he could truly feel alone. The moon was big tonight, he noted. It was funny to him how humans took pride in making guesses about the planets and outer space. To him, it served a purpose of peace.

Not thinking of the vision, he closed his eyes again, and was enveloped by the comforting darkness and the moonlight. Everything was the way it should be. He had his family, and they had a job. Nothing else to it. But he knew, deep in his heart, that nothing ever stayed the same for long.

The air around him dropped in temperature and he crouched below the fronds of the wheat plants, dropping his angel blade into his waiting grip. Something blocked out the light of the moon and stars. It was coming closer, dragging something through the fields. Electricity crackled, and the atmosphere seemed moist, like a storm was coming. There was a crackle of thunder, and it started to rain.

This sent multiple alarm bells off it Cas' mind, but he managed to hold his breath as the supernatural being stopped a few yards from his spot. Then, knowing it would be better for him to attack first, Cas leapt to his feet and charged the dark figure. In the nick of time, it turned around, and he stopped dead in his tracks.

It could almost pass as an angel, but it was not. It didn't seem to have a vessel, just existed as a dark humanlike figure with cold violet eyes. And its wings…they were snapped, broken, helplessly hanging off the it's back. Castiel stepped back, but kept the silver blade between the two, using its light to see the figure, as it blocked most of the natural light.

"Who are you?" he whispered gravely. Then, for added measure, with a tint of threat in his tone, "What are you?"

The figure narrowed its purple eyes to thin slits. "I am an Thunderbird. We take no names. But I know yours, Castiel. I know all about you."

Cas took this as a bad sign, and adjusted the knife, preparing to throw it. "I wouldn't try that on me," the Thunderbird advised. "Angel blades do no harm to us. That's better," he added, once Castiel reluctantly drew the blade back up his sleeve.

"Now," the Thunderbird said calmly. "We have much to discuss." Castiel met its gaze with conviction and began glow, his grace ringing as his eyes burned white, clearly displaying his power. The Thunderbird only twitched in amusement at the spectacle. "Angels."


	2. Chapter 2

Cas didn't hear what the Thunderbird said, and didn't care. He concentrated on his growing powers, trying to show his opponent that he wasn't something to be messed with. His eyes were a burning white, and he felt the ghosts of his wings rise behind him, illuminated in the light of his grace.

The Thunderbird was still. Cas didn't like that. He held his stance, waiting for the dark figure to act. And he did.

It started with a huge booming crescendo of thunder. Cas realized the sudden storm would have woken the Winchesters, and they would know he was missing. But he had bigger problems than them now. The Thunderbird was swelling up, like a bird puffing up its feathers to act bigger, except this was no act.

Its eyes glowed like Cas' did, but the lavender light was now a dark plum. The storm intensified, and the thunder was almost constant. Cas growled under his breath and stood his ground. The Thunderbird stretched too, its dark arms reaching skywards, but its wings were still stuck on the ground.

This seemed like a sore topic for the Thunderbird, who stood tall with pride, even though his wings were badly broken. Cas decided that this might serve as a good break in their showoff of strength.

"What happened to your wings?" he shouted over the sound of his ringing grace and the thunderstorm erupting around them.

There was a pause in the storm, and the violet eyes showed a sign of defeat. The Thunderbird shrunk back down to a human sized form. Castiel took this as a good thing and cut off his grace from humming so loudly and returned his eyes to their normal blue. However, he made sure to keep the mirage of his wings up, a bold sign of dominance.

A thunderclap jolted the Thunderbird out of its frozen glare. It stepped forwards, undeterred by Castiel's widespread wings. Just as it was about to speak, it jumped and turned around nervously. Cas heard it too. The distinctive purr was of a 1967 Chevrolet Impala cutting through the fields towards Cas and the Thunderbird.

"It's okay," Cas said irritated, tucking his wings back in their plane of existence. "I'll go talk to them. You stay where you are."

The Thunderbird didn't reply, and retreated a few steps, eyeing the sleek black car with distrust. Cas honestly felt bad for it. Behind its cruel looks, there was something terribly wrong. He felt safe putting his back to the Thunderbird and walking to the parked Impala, its windshield wipers flicking away the downpour.

Dean raised his hands and mouthed through the glass, " _What the hell_?" Sam nodded in agreement and pointed to the wary Thunderbird in the distance. Cas got in the car and slide in the middle, so he could see both brothers. "I- "

"Cas, seriously," Dean cut him off with a growl. "I agreed to a nice nap in the countryside to get away from weird crap, not to discovering new types of monsters who can control the friggin' _weather_!" It was awkwardly quiet, as Cas tried to think of a good response. The Winchesters waited. Through the rain, Cas could see the Thunderbird watching them.

"Here me out," Cas started off slowly, trying to ease Dean's rattled nerves. "Just…let me explain everything."

Dean and Sam exchanged worried glances, and Cas frowned. They were skeptical about this whole thing, but he didn't blame them. "I..." he struggled to create an excuse for running off. "Wanted to think about some things. It- "he gestured towards the purple eyed Thunderbird, "came when I was off guard. Maybe it was drawn to my grace. But believe me, I don't know anything about its kind, or what it wants."

"Wait," Sam intruded. "What even is it? I've never seen anything like it before.?

Cas shrugged. "Neither have I. It's something called a Thunderbird."

Dean cut their silence with a laugh. "Hence this crazy weather."

"Yes," Cas agreed. "Its powers do seem tied to nature. But Dean, there's something not right with it."

"Oh," Dean said. "Like the fact that it's a freak with freaky purple eyeballs who can make freak thunderstorms out of nowhere? Yeah, Cas. This isn't right. How do we kill it?"

"No." Cas hissed. "You don't understand. I saw its wings. They- "

"Great!" Dean was practically shouting. "And it can fly!"

"What is it Cas?" Sam slapped his brother and gave him a warning look. "What's the matter?"

"I saw its wings," Cas repeated firmly, stretching his head between Sam and Dean's. "They were _broken_. It's in pain. It needs help. I was trying to talk to it, before you two frightened it."

Dean rolled his eyes and pressed down on the Impala's horn. "You scared yet, freak?" he hollered. Cas and Sam cringed as the Thunderbird's wings frantically backpedaled and it almost fell on its back.

"Okay," Sam said in a deadly quiet, serious tone. "Dean, stay in the damn car. Cas and I will go talk to…it."

"Whatever."

Cas wanted to say something, but couldn't find words to fix the situation. In unison, he and Sam left the car and entered the lightened drizzle of rain. They walked towards the Thunderbird, whose stance was lax, and appeared as dangerous as a clipped bird.

"Hello," Cas initiated the conversation. "I apologize for all of that," he motioned to Dean sitting in the Impala, blasting music. "Sam and I would like to talk to you, especially about your…problem."

"You mean my wings." The Thunderbird weakly ruffled his feathers knowingly.

"What happened…um…what should I call you?" Sam looked nervous but attempted to smile at the Thunderbird politely.

"My kind take no names," it replied, cocking its head in confusion. "My wings are the only reason you are even seeing me at all. These are bad times for my people, my flock. Bad things are happening. I was chosen to find help. I tracked something, something that turned out to be the angel Castiel. And now, to Sam." It paused.

"I am sorry if I frightened you, Castiel. I did not know how to properly approach an armed angel. I do not know if your blade would have any effect on me. I had to lie. That was not who I truly am."

Cas was taken aback by the creature's docile apology. He nodded an "It is alright. It was simply a misunderstanding. I am sorry for pulling out the blade in the first place."

"Guys," Sam said. "Look, I'm happy that we're all friends here, but if this is going to take a while to sort out, we better head to the closest town. Uh..." he glanced at the Thunderbird, it's dark shadowy body barely resembling a person. "Can you change into something more realistic? No offense, but it'll be easier getting you into civilization."

The Thunderbird let out a small chuckle. "I haven't done this in a very long time. I was lucky to gain this body. I shall try. One moment, please."

He closed his eyes and the darkness dissipated and in its place, was a young black-haired man wearing combat boots, black jeans, and a midnight hoodie. Sam's eyes widened. The Thunderbird could almost pass a very emo human. The one thing that was wrong, was that his eyes were still bright purple. Oh well. If anyone asked, they'd say they were colored contacts.

Cas noticed too, but chose not to point out the Thunderbird's mistake. "That will work. Before we go…" he asked tentatively. "I think we're both quite curious. What is it that is making these times so bad for you and your kind?"

The Thunderbird shivered, and it stopped raining altogether, though the clouds were still grey. He turned his violet eyes to lock in to Cas'. They were wide with fear.

"Hunters."

Sam stiffened. Cas was shocked into silence as well. Neither said a word. Finally, Sam snapped out of it and smiled again at the Thunderbird, "We should get to the car. Give me a minute to… talk to Dean first, though. He is not someone you want to surprise." He said this last part lightly, trying to ease the Thunderbird's obviously dislike of his brother.

The Thunderbird narrowed its eyes, associating the honking with Dean. Cas saw its untrusting face turned towards the Impala, where Sam was leaning in the driver's window, whispering to Dean, who seemed less than pleased with what his brother was saying.

"It will be alright," Cas ventured, walking up to the Thunderbird and putting a hand on his shoulder. The Thunderbird tensed from the touch, but forced his muscles to relax. His violet eyes bore into Cas' blue ones. "I trust you, Castiel. I do believe that you can help me. And if that means I have to deal with an annoying human, so be it. I must do this."

Cas nodded and looked back to the car. Sam was backing away from it. He turned to the angel and the Thunderbird. "Let's go."


	3. Chapter 3

It was not the oddest assortment of beings the Impala had ever carried, but it was a new one. The Thunderbird sat anxiously next to Cas in the backseat. Dean ignored it, but Cas wasn't worried. He knew Dean would come around in time. That's why he almost jumped when Dean cleared his throat, and huffed sarcastically, "So, Boomer, where you from?"

The Thunderbird glanced at Cas, confused at the nickname. Cas gave a slight tilt of his head encouraging him to talk. "Well," Boomer said. "My flock resides on the top of the Rockies."

"Huh." Dean grumbled. "And how come no one's ever seen you guys before?"

"We do not like humans," The Thunderbird replied coldly. "We do not wish to hurt them or scare them or let them find us. That's why we live in such bitter conditions. But someone did find us. And now they're hunting us, one by one."

"Boomer," Sam cut in, easily accepting the nickname given to him by Dean. "Who did that to your wings?"

The Thunderbird twitched. "Hunters," he repeated angrily. "They hit me as I was flying down the mountain. I had to travel on foot to track down Castiel."

Cas' acute sense of hearing could barely pick up Dean's muffled hiss to Sam, "Hunters are supposed to be the good guys, not the other way around. I don't trust Stormy back there." Boomer slowly turned to look out the window and Cas knew he had heard Dean's comment.

"But," Cas growled, feeling defensive because this was almost the exact same thing Dean felt when he discovered the existence of angels. "They are peaceful. They do no harm to people. That's why we never had heard of them before. Because they are not _dangerous_."

He expected a fierce speech about the family business. Saving people, hunting things. All about how evil deserves to die, and how Boomer was evil, down to his core. But Dean only tightened his grip on the steering wheel and gunned the engine, so they were flying down the highway, heading into the rising sun.

Boomer's eyes were glued to the window. Cas knew what he was feeling, how unnatural it was to be moving at such a speed, but to be along for the ride, to not be the one in control. He knew he could fly again, but there was something about Dean's baby that he loved, and apparently Boomer felt it too. He couldn't help but think that he and the Thunderbird had a lot in common.

Sure, the Winchesters had reassured him again and again that he was like a brother to them, but he knew that there was still something that separated them. It wasn't surprising. He understood their small bits of doubt towards him. He wasn't human, it was simple as that.

The rest of the ride passed without any more conversation. Dean pulled the Impala into the first motel they came across just as the sun extended fully out into the sky. He glanced at Sam, who gave him a quizzical expression.

"Wanna get checked in?" Dean pushed.

Sam jolted. "Oh. Yeah, yeah, I'll go do that. Right now."

"What is this place?" Boomer asked cautiously, as Sam squeezed his lanky frame out of the Impala and hurried towards the office.

Cas jumped on the question before Dean could snap something sarcastic at him. "A motel… is like a little home that's used in travels."

"Huh."

When Sam got their room number, and everyone had helped unpacking the trunk except Boomer, Dean locked the motel door and whirled around, anger flashing in his gaze, with a pistol pointing at the Thunderbird. Sam and Cas froze. Boomer looked at them desperately for help, but they were transfixed on Dean.

"Okay, stormy. Here's the rundown. One. I don't trust you. Two. I don't have a damn clue why I agreed to help you. Three. You obviously are dangerous. Scared _Cas_ , a freaking angel warrior." He saw Cas' wide eyes. "Yes, feathers. I saw your macho standoff."

"Now," he growled viciously, unlocking the safety. "Stay still."

And then he fired.

The Thunderbird peered down and inspected his body. Dean rolled his eyes in exasperation. His bullet had been perfectly aimed, it should have gone straight through Boomer's heart, but his white shirt didn't even have a hole in it. "That was incredibly rude," he snarled, eyes narrowing to angry slits. "You should not have done that."

Dean didn't look surprised. "Well, piss off then, you friggin' monster. Fix your own damn problems."

Sam and Cas exchanged a quick worried glance. They had to try something, before Dean riled the thing up so much it killed them all.

"Boomer," Cas said, trying to channel his angelic aura of authority and wisdom without spooking him even more. "Wait- "

"I am sorry, Castiel," the Thunderbird snorted. "But I know _you_ are the only one who can help me. There is no other being powerful enough to do any good. And that miscreant," he pointed accusingly at Dean, who rolled his eyes again. "Will make everything worse. If you truly have a good heart, and want to help my people, please come with me."

Sam touched Cas' shoulder. "Cas. You know you don't have to go." Dean just stared at Cas, probably expecting him to jump on the Winchester's side. Boomer's wide doe eyes pleaded silently. It wasn't easy, but Cas knew what he had to do.

"I have to go," he whispered, ashamed for his betrayal to the Winchesters. "I'm sorry Dean but I have to do this."

The elder brother wouldn't take that for an answer. He immediately stood right in front of the angel, and angrily shouted, "Why, Cas? Why trust this _freak_ after knowing it for a couple of hours, while you've known Sam and I for years?"

"None of your business," Cas' reply was smooth but chillingly unsympathetic. Then, regretting his harsh tone, he quickly added, "I'll be in touch."

With that, he took the Thunderbird's arm, looked regretfully into Dean's bottlecap green eyes, then disappeared with a whoosh of feathers, leaving the two brothers standing dumbstruck in a motel room they had no more use for.

Or so they thought.

 **Thanks for reading! Please don't be afraid to follow or favorite. Shoot me a review if you like how it's going so far! It really keeps me going. Thanks again :)**


	4. Chapter 4

When Dean had finished cursing about friggin' angels and how stupid Cas was, he mumbled something to Sam about getting some food. He left, slamming the door just a little bit. Sam sat at the desk and tried not to worry. His brother was so protective of his family, sometimes forgetting they all could handle themselves. Well, usually.

With nothing to do except wait for the roar of the Impala to return, Sam thought back to what Boomer was talking to in his pitch to convince Cas for help. He opened his laptop and began to search for some Thunderbird lore.

He didn't find much. There were a few accounts of eyewitnesses claiming giant birds the size of small commercial airliners, but the best supernatural info he could scrounge up was that they were of Native American heritage, and could shift into people. He also noted that in every sect of native religions, they could control weather.

Then he finally found the dirt. He quietly shut the screen and rubbed his eyes and rested his head on his arms. Without realizing it, he slipped into sleep. In the first time in a long time, he dreamt. And not surprisingly, it was a nightmare.

It started pleasant, on a snowy mountainside. Then he saw Cas and Dean, who were having what looked like a one-sided snowball fight. He smiled as his brother slipped again and was immediately pelted with two snowballs to the face.

But it didn't last. Dark clouds rolled in, freakily fast, and he couldn't see Dean or Cas. In the sky, a bright purple figure in the shape of a massive eagle dropped to the ground. It's cruel violet eyes seemed to taunt Sam and it faded into the darkness.

Sam tried calling for Dean and Cas, but no one answered. Then, as suddenly as it came, the clouds peeled away, revealing Cas standing at the edge of the woods. Sam had a bad feeling about the copse of trees, but he was unable to stop Cas from glowing white-blue and marching into the forest.

He heard a noise unfitting to the dream. A loud rumble. The Impala. With a start, he woke just in time for Dean to unlock the door and drop the bags onto the table.

"So," Dean grunted, as he unwrapped a burger. "Anything?"

"Uh, yup," Sam replied. "Get this. Thunderbirds delight in fighting and causing mischief," he said, reading off his notes. "And punishes humans who have broken moral rules."

"Dammit."

"You can say that again."

"Dammit."

"Cas isn't a human, Dean. Boomer has no reason to hurt him. Like he said- "

"Yeah, yeah, the bird people are in trouble and they need our bird person to help. I still don't like it, Sam. How'd Boomer even find us?"

"Well," Sam said slowly, working the problem out in his head. "We hadn't heard of his species before, so we couldn't ward them off, right?"

"I guess."

"Why don't you call Cas, just to update him on his travel buddy?"

"Good idea." Dean flipped open his phone and dialed Cas. He tried twice before growling in frustration and leaving a snippy message.

"While we wait for the idiot to call back," Sam suggested. "Let's eat, and do some more research. No point just sitting here and twiddling our thumbs."

Dean agreed with a nod and they set off to work. When he hit his third beer, Sam got an idea. He closed his eyes and prayed to Cas.

 _Castiel. Cas, you copy? We did some digging, and Thunderbirds definitely have major weather powers. No joke. And Cas? They feed off of fighting and mischief and people who haven't followed their idea of "moral rules." Seriously, Cas, be careful. Call us._

 **Sorry it's short!**


	5. Chapter 5

Flying with Boomer was not fun, as flying usually is. As soon as they took off, Boomer practically dragged him through the ether. It made Cas a little dizzy. They landed in a small yurt with windows showing off an impressive view of a valley full of lush wildflowers.

"What is this place?" Cas asked, striding around the room to take in his surroundings.

"A safe house."

Cas took this in. He glanced around the room and saw the thing that didn't click. "Why aren't more of your kind here, if the mountains are so dangerous?"

"They are here, Castiel. They are just hiding."

This freaked Cas out, but he said soothingly, "It's alright. I'm here to help."

Nothing happened. Boomer's body melted into darkness and emerged as the giant ravenlike man with matching purplish wings and violet eyes. Then, out of thin air, about a dozen more forms took place, all forming a circle, with Boomer at one end and Cas at the other. Some were female, with magenta feathers and silvery pupils, and there were three smaller ones, whose wings were full of fluff.

"This is what's left of my flock," Boomer explained sadly. His tribe nodded gravely.

"Well," Cas said. "What can you tell me that will assist me in helping you?"

A fierce looking woman with electric pink wingtips spoke up. "When it first happened, we thought it was a coincidental accident. The Thunderbird involved was known for being a little too…" She blinked at her peers, and when they nodded, she continued with a slow exhale, "uncareful."

"And stupid," another added with a snort.

"So," she rallied. "We wrote it off. Life for us went on as normal. But then the next week, it happened. Again. And again. After the third time, we were all on full alert."

"Nothing could stop them," a small one whined. "They took my sister."

"Them?" Castiel butted in. "You are sure this is a group effort?"

A few Thunderbirds exchanged bemused glances. Boomer smiled. "Like I said before, we are not a force to be reckoned with. It would take a team of highly trained individuals to even find us. We haven't seen anything like this ever before. When hunters of the supernatural came about, we could have killed them all. But, it was decided to live in the mountains, and to not bother humans again, unless they bothered us, of course."

Cas twitched. Boomer looked pleased, but Cas wasn't spooked at Boomer's ominous words. He listened to someone praying to him. It could only be a few people.

 _Castiel. Cas, you copy? We did some digging, and Thunderbirds definitely have major weather powers. No joke. And Cas? They feed off of fighting and mischief and people who haven't followed their idea of "moral rules." Seriously, Cas, be careful. Call us._

Boomer noted Cas' unfocused eyes. "Castiel?"

"Yes?" Cas replied, a hint of fear escaping into his word.

"We would like you to find these people." The circle murmured their approvals. "They might not be equipped to handle angels. You are a rare species, just like us."

Cas let the effect of this to sink in. Boomer was more than gentle after their initial encounter, but there was something off about the predatory eyes that kept locking into his. Paired with the prayer, he was almost doubting his sanity for coming with the Thunderbird.

"How will it help me?"

Boomer laughed. "Spoken like a true rebelled angel." He grinned mischievously. "Well, for starters, I won't kill your friends."

"No," Cas hissed, his grace humming with rage. "You tricked me."

The circle laughed. Boomer held up his hand. "I guess you can also take comfort in the fact that you have a good heart. Soft, too."

Cas' aggressive nature emerged. He was through being fooled with, having the Winchesters on the line, forced to work for other creatures. "No," he repeated.

"Well," Boomer snapped back. "I think I must insist."

With that, the curtains snapped shut and the circle pushed Cas into the middle, who began to turn to face each Thunderbird. The shadows of his wings materialized behind him, his eyes glowed a burning white light, and he grasped his angel blade. "I must be going," Cas snarled.

At that, each Thunderbird raised their inky wings and made a cage of black surrounding the angel.

"You will," Boomer promised, his voice echoing over Cas' grace, whining to fight. "But not back to those two idiot humans. To find the hunters, and cut off their heads. I like my trophies." He smiled, the purple lighting casting eerie shadows on his face.

Apparently, he wasn't done with his speech. "Also, we will have scouts on the Winchesters around the clock. Any attempt at calling for help will result in something extremely unpleasant. And Castiel?"

At this point Cas couldn't think of anything to make his situation worse. But Boomer did. "You have three nights. If it isn't done by dawn of the third night, Sam and Dean die."


	6. Chapter 6

"So," Dean grunted nonchalantly, stuffing another piece of bacon into his mouth. "Cas should have called by now." He eyed his brother as he chewed, daring him to say what he didn't want to.

Normally, Sam would have teased Dean about his eating habits but instead he picked at his omelet and shrugged. "Yeah, I don't think total radio silence is a good thing."

"Uh huh. And you know he kind of jumped the gun when that walking shadow started yammering about goodness and crap." Dean tensed, trying to think of a way to put his next words. "I'm afraid that Cas agreed to do the T-Bird's rain dance just to make up for things he thinks he did wrong."

That did sound like the sort of trick Cas would pull. Unfortunately, even though his intentions were good, the outcomes created more problems than they solved. Case point, when Cas stayed in Purgatory to do "penance." One thing led to another, and next thing they knew Naomi almost got Cas to kill Dean.

"Well," Sam said flatly. "That's the sort of thing Cas does, right? It's who he is."

"I don't like it."

"Neither do I, Dean. But we can chew the idiot out for being, well, an idiot, when we get him home."

"Wait," Dean said in all seriousness. "You do think those Thunderbirds did something to Cas?"

Sam ran a hand through his thick hair. "Honestly, yeah."

"We gotta do a locating spell, then," Dean grumped, slurping up another cup of coffee, "And find out what's really going on with the Thunderbirds. I knew that new breed of weird wasn't going to pan out well for anyone."

"Dean," Sam said, pushing away from the table, having already paid the check. "We can worry about them once we know for sure Cas is okay. First things first. Let's go."

In perfect sync, the two got up from their table, and walked to the parking lot. The Impala sat proudly among the newer, boring models, and her engine purred right to life as Dean cranked it. On the way back to the motel, neither said anything. Rock music filled the empty space, though without the usual calming effect.

"Wait." Sam jolted. "We, uh, never really used an angel tracking spell before. It is even possible?"

Dean grinned slightly. "They always said that you are the smart one, but I've seen a ritual before. Remember when Cas found Balthazar? I wrote it down. I bet that can work on Cas."

"Okay…but are you positive humans can do it?"

"I don't care, Sammy. If there's a chance that it'll get us to Cas, I'll take it."

Sam nodded. Whenever his brother got his mind to something to help someone he cared about, no matter how stupid or dangerous, there was no turning back and no convincing him otherwise. Dean pulled the Impala into park and got out to go gather necessary items from the trunk.

Together they carried the ingredients into the motel room and prepared them for the spell on the table. Dean whipped out a big black marker and wrote a sigil on the table. Sam watched as Dean put an iron bowl directly on top of the symbol.

"What are the ingredients?" Sam asked curiously. He didn't remember what Cas had used. His soulless self apparently didn't feel the need to learn angelic tracking spells.

"Three pieces of myrrh," Dean replied, putting the said myrrh into the bowl. Then, quick as a viper, he slashed his own hand with a knife and allowed the blood to periodically drip into the container. "And human blood."

"What ne-"

"Shush."

Dean turned to the piece of paper laying on the table next to the bowl. "Zod ah mah rah na ee es lah gee roh sah." He closed his eyes, mimicking what Cas had done.

After a few seconds, and Dean still hadn't moved, Sam nudged him. "Dude, did it work?"

"Son of a…" Dean grumbled, rubbing his closed eyes. "It worked all right."

"And?" Sam sputtered, throwing his hands in the air exasperatedly. "Where the hell is he?"

"Uh… Hotel Talisa. Damn. Sounds fancy." He plopped on the nearest bed and did a quick search for the location.

"Well," Dean said with a sigh, still skimming the screen. "It's in a ski town called Vail. About seven hours from here. And get this: Vail is experiencing a serious snow drought. It's all over their news."

"Sounds like some pissed off weather birds are hanging out there," Sam responded. "If we leave now, we can get there in good time and hopefully figure this whole thing out by dark."

"We leave in five," Dean announced as they both silently thought that their problems were never solved very quickly. "Let's go get Cas."

Five minutes later, the taillights of the Impala were fading down the two lane road, headed to the Rocky Mountains. Halfway through the journey, Dean pulled over and switched with Sam. Another fifteen, and he was snoring in the shotgun seat.

They didn't stop for lunch, and it was just them and the road and the Impala for another seventy miles when Sam heard a hitch in Dean's snoring. He didn't think much of it, and concentrated on driving, but it happened again. This time, Dean jerked a little. He mumbled something and shot upright. "Wha-"

"What, Dean?" Sam asked, furrowing his brows. He hadn't though much about the nightmare about Cas and the snow, but it hadn't meant anything.

"I saw Cas, dude. On a mountain. Something was wrong."

Sam inwardly tried to suppress his panic. Yet he couldn't bring himself to hide his dream from Dean when Dean shared his as soon as it happened. Sure, Sam had been alone in his, but he wanted them to trust each other. No secrets.

"I think I know what you're talking about."

 **Hope everyone still enjoys :)**


	7. Chapter 7

Cas touched the shiny piece of plastic given to him by Boomer. He recalled the instructions as he walked towards the lobby. A doorman jumped up to open the glass doors for him. Inside, he was welcomed by a cozy cabin feel. It was around dinnertime, so the restaurant was teeming with activity and there were lots of people lounging in chairs and sofas around a fire and a television.

He took all of this in and walked to "check in" as Boomer put it. The lady at the counter smiled as he walked up. "What can I do for you today, sir?"

"I'd like a room."

"Okay," she said. "Reservation?"

"Yes. Under Birdman." Cas cringed at what even he knew was a horrible joke played on him. "I believe I have three nights."

"Sure do, Mr. Birdman. Your room number is 510. Enjoy the suite. Do you need assistance with your luggage?"

Cas cocked his head. Boomer didn't say anything about luggage. Sam and Dean never stayed in a hotel, so he wasn't familiar with this term. "No," he replied, to be on the safe side. He took the key card, and walked to the elevator.

When its doors opened with a click, a young man with mocha colored skin strode out. His doe eyes bore its Cas. They flashed purple as he passed by. Cas narrowed his blue eyes and entered the elevator. He rode up to the fifth floor and followed the signs to 510.

It took him a few tries to get the door to open for him, but he finally got the green light. Inside, the room was furnished in a modern ski resort fashion: white furniture, forest animal décor, and vintage wood artwork. A massive glass window displayed picturesque mountains in the distance. But that wasn't what he was interested in.

On the desk, sat piles of manila folders. A purple sticky note read _We also want proof of your success other than you word. Perhaps the things they stole from us? Good luck, Castiel._ Cas growled. These Thunderbirds were really getting on his nerves. He felt the heavy weight of loneliness on his shoulders and longed to at least call the Winchesters. But Boomer had thought this out very well and had take Cas' phone before he sent him to the Hotel Talisa, as a firm reminder of his isolation.

Cas settled down, and opened the topmost folder. A newspaper flopped out. There was a tab, and Cas flipped to the story.

 _On a cold evening in Vail, while sitting on his porch facing the Rockies, a local claimed to spot a bird with a wingspan of over fourteen feet. The local, Edward Clarke, says that he found a feather from the beast, who he believes to have been wounded, judging from its "awkward flight pattern". Bird experts insist that the feather is simply from a mutated form of vulture. This is the third sighting of a mysterious bird that Vail has experienced in the past week. Some native peoples claim the creature is one of unworldly proportions, something called a Thunderbird. These sightings, no matter what you think of them, are still causing quite a bit of conversation around town, along with the never-ending snow drought._

He absorbed this information, shifting in the spinning chair. Boomer must have put this here as a clue to find the hunters' location. Cas didn't know why Boomer couldn't have just given him some directions, but this newspaper would have to do. He put it to the side and opened the next folder.

To his surprise, there were locations of possible suspects. The rest were various maps with pink marks to where Thunderbirds went missing, and purple stars for human sightings of Thunderbirds. Cas decided to fly to interrogate the witnesses in the morning. He would go from there.

Then he spotted something that he didn't see before. One of the desk drawers had a piece of paper sticking out from it. He scanned it and numbly let it float to the floor. They were watching Sam and Dean, and were prepared to kill if Cas stepped a foot out of line.

Out of nowhere, while the room began to darken as the sun set, and the stars came out, Cas heard someone praying to him. He was surprised. He had expected for the Thunderbirds to find a way to cut off incoming messages.

 _Cas._ It whispered. _We know you're in Vail. We're coming for you buddy. Don't worry._

"No," Castiel winced. "They'll kill you both." There was no way of warning them. Cas gritted his teeth. He would start looking in the woods tonight. He had left them in Arkansas. It would take a hell of a long drive for them to reach him. Even with Dean driving, he still doubted they would arrive before dawn. He had to get to all of the hunters before then.

In an instant, he appeared at the edge of the woods, in front of an address he found circled in the folders, whose lights were still on. He knocked loudly. "Hello?"

No reply. He barged through the door to face a stony-faced man dressed in plaid, pointing a gun to Cas' chest. "Try me," Cas growled impatiently. The man fired. Cas didn't even blink as he plucked the weapon from the human and tossed it aside.

"What the hell are you?" The guy whimpered as he crouched in the corner, wide eyes fixed on the bullet wound right over Cas' heart.

Ignoring him, Cas searched the house for evidence. When he bust open a safe, he pulled out a bundle of massive purply feathers. His own wings twitched in discomfort and disgust. He went back to where the man lay. He considered sparing the idiotic human, but the Thunderbirds' message had been clear, so he smote the hunter.

Little did he know, is that the idiotic human had made a few phone calls while the angel searched his home. His judgement, his logical thinking was clouded by his worry for the Winchesters. He popped to the next address.

This time, it was in a hill billie looking residence, with a rusting roof, no trespassing signs, and litter scattering the yard. Cas marched right up to the door and smashed it to pieces. Someone screamed and hit him with an ax, but Cas hardly even noticed. He knocked out the woman with the ax, and the five small children flanking her, and held the hunter against the wall.

"I need your trophies."

"Like hell you do, boy," the hunter snarled, whipping out a pistol and hammering Cas in the chest. And like the first, looked in horror. "Rory was right!" he said in astonishment. "The weirdo in the trench coat is- "

"No need for your input," Cas butted in. "The Thunderbirds send their regards."

With that, he smote the guy down. It didn't take long to locate the pair of wings hanging over a large mattress with furs and blankets spread on top of it. He slipped them next to the handful of feathers into the ethereal plane.

As he stepped outside, he noticed that it had begun to snow. He stood, taking in the beauty of the pale flakes falling on everything in sight, including him. It was impossible for him to feel cold, but he could still appreciate the natural wonder occurring right before his eyes. He was so lost in thought, he didn't think about what the hill billie said about Rory.

 **Hope everyone is still liking! I got more ideas for the plot. It's gonna get so good!**


	8. Chapter 8

The sky was beginning to show off the telltale pinkish glow of dawn as the brothers entered the cheapest looking motel they could find. At the counter, an elderly woman was reading the newspaper. She peered at them from behind her bifocals. "What can I do for you boys?"

"A room, please," Sam said, stifling a yawn.

"You here for skiing?" she asked, as she wrote something down in her logbook.

"We're researching the weather," Dean cut in. "For a scientific…study."

"Ah," the woman sighed, handing them a set of keys. "Yes, it's been not good for business. This is usually our busiest time of the year, but without fresh powder, folks have been going to Aspen and Beaver Creek instead."

Sam put the keys in his pocket. "Thanks."

They swiftly unloaded the Impala and set up shop in the motel room. After everything was ready, Dean turned to Sam. "We should go to the Talisa, check Cas' room."

"Sounds good."

A few minutes later, after passing gaggles of hitchhiking tourists heading to the slopes, they found the hotel. Dean and Sam walked in, flashed their badges, and asked for the room number for a dark-haired man with blue eyes and a trench coat. The lady at the desk pointed them on their way.

"Nice place," Sam commented, a little in awe of the luxurious accommodations of the lobby area. Dean only grunted in agreement as they rode up to the fifth floor. They hurried to open the door to 510, and gaped at the size of it.

It was evident where all the important items were. The desk. Cas had memorized the info, so he had left it out in his hurry. Dean and Sam read bits and pieces. When they found the note mentioning that they were being watched, Dean stomped his foot. "Those sons of bitches," he snapped, "blackmailed Cas against us, to do their dirty work?"

"Dean," Sam said. "We have to find him."

"He could be anywhere, Sam! Most of these places look off the grid types. It's like a T-Bird hunting cult! If they can take down things like Boomer, what do you think they can do to angels?"

"Nothing good."

"Well," Dean replied softly. "What the hell are we waiting for? We'll start checking addresses. Let's go. Cas needs us."

When they got back on the road, Sam leafed through John's journal, desperate to find any mention about Thunderbirds and how to kill them. He came up empty.

"I'm going to call Bobby." Dean nodded. It would take them a while to get to the houses. While Sam started to explain their situation to Bobby, and talk about lore that might help, Dean's eyes were fixated on the mountains surrounding them. They reminded him of Cas. Strong, cold, and full of mystery. He prayed again.

 _Don't worry, Cas. We know about your problem. Sammy and I are coming for you. Please, don't do anything stupid. Wait for us._

"Hey Dean," Sam waved his arms in front of his brother. "Bobby said that he knows about Thunderbird lore, but doesn't have any records on how to kill one."

Normally, Dean would get angry, but at this point, he didn't care. "We'll just have to try everything," he shrugged.

An hour later, they found the house. Smoke swept up from the chimney. Sam squinted. "The door is open."

"Great."

They steadied their guns, but relaxed when they nudged the door open. A man in camouflage garb was dead, his eyes burnt out. The rest of the house was unoccupied.

"The next house is in a sketchy area," Sam commented, as they drove down the driveway, eyes devouring the map. "It's in a little campground far from the nice touristy stuff."

"Great news."

The house was a dumpy little thing, with only a blanket covering where the door used to be. The brothers exchanged worried glances and advanced. Inside, they found a pair of small children who scurried off to the back room. A woman with greasy hair stormed in with a pistol. "Get the hell out!"

"Wait," Sam gasped. "We're trying to figure out who killed your husband! We know it wasn't human!" As he said this to get the lady to put down the gun, he cringed. It sounded like they were on a regular hunt, trying to convince a victim's family that the thing that killed their loved one was something supernatural. In this case, it was their friend that they were hunting.

"Yeah," she whispered, stroking the hair of a young boy who cuddled up to her leg. "He looked normal enough, but he knocked me and my babies out without touching us. When I woke up, Ron was dead."

"Did he say where he was going?" Dean pushed.

"No, but he did take the wings of the vulture Ron shot a few days ago. They were really big ones, too."

"Thanks," Sam and Dean said simultaneously. The woman waved her gun at them again. "Get out."

With that, the brothers turned tail and exited the house. Sam stopped and observed the yard. "It snowed here."

"Yeah, so?"

"There has been a snow drought. This has got to be at least five inches."

"Great, so Cas murdered a dude, and the Thunderbirds are happy? Is he their hitman?"

"I don't know. I hope not. Those things are notorious for being tricksters. I bet they have something worse planned."

"Let's get Cas before they have a chance to do anything worse."

The Impala's shiny midnight black paint stood out against the pearly white snow. Her tires squealed a bit as they fought for traction, but with Dean at the wheel, they were on their way to the next house in no time.

"Hey Dean," Sam stated after the house was far behind them. "Cas can fly. He's a lot faster than us. I think the only way to catch him is going to the last place on his list. The one farthest away from civilization. He obviously knows the map by heart, and seems to be working his way more and more rural. We have one chance, Dean."

"Okay," Dean replied coldly, easing his foot on the gas. "Where to?"

"It's a pretty high elevation, so cold that snow stays on the ground year-round. I bet it'll be protected and the occupants won't be happy to see us."

"Let's go."


	9. Chapter 9

Cas smiled in satisfaction as another hunter's eyes burned out. He thought the Thunderbird's request would have been a much more difficult challenge, but he pieced together what happened from the pleads of hunters. One, who was of Native American descent, got a hold of a spell from his grandfather. They used it to find and kill Thunderbirds.

 _We're close, Cas. Hang on._

Cas stiffened. Close to where? If they had gone to his hotel room, they have to have seen the warnings. He could handle this himself. He was almost done, too. Only one more person on the list. The Winchesters were his family, but they overlooked and underestimated him.

For starters, they never bothered to think how difficult it was for Cas to drag Dean out of hell, and what the cost was. Cas fell from heaven because he got too attached to them, even though they probably didn't feel the same back.

Then, when Cas was resurrected by Chuck, he was turned into a seraph, a whole new level of angel. Of course, he hadn't told the Sam and Dean, but it just didn't seem like they appreciated him very much. He also never forgot when they hated him, when Sam threatened to kill him if he didn't help them. That they always called him when they needed something, not to check on him.

And then when he was at his lowest, when the angels fell and he was human, Dean had kicked him out, then refused to hunt with him. It still hurt. This was Cas' way to show that he could handle himself, that he wasn't the Winchester's pet who could attack on command

He was a seraph, a fearsome warrior of heaven, and he would prove to the whole damn world that he was strong.

Snow immediately began piling on his shoulder when he landed at the last location. The house was quite large, with all the lights still on. He strode forward, he knew they probably expected him, so he didn't want them to escape. The door swung open a few feet before he reached it. His grace sensed his aggression so it was jacked up with strength.

Cas stood in the entry hall. It was an open concept house, with hardly any closed doors. He didn't even have to check upstairs. A man in a suit walked calmly towards him. "We've been expecting you," he remarked, holding his hands out in victory. "Castiel."

Ignoring him, Cas positioned his angel blade in his hand, aimed, and let it fly. Its path was true, the silver knife hit the man in the heart and his ribcage sparked and cracked as the demon inside died. Cas whirled around to find a pair of men. One dropped a match, but Cas flew out of the circle of holy oil before it caught on fire.

He stood with his back to the full-length windows at the back of the house. The demons advanced. Cas held his angel blade up. A few yards away, they stopped. They were waiting for something.

Another figure strode elegantly down the stairs, taking his time, watching Cas intently. He carried a bow and a single arrow. Cas was silent as the demon stood between his minions. His vessel had green eyes, a painful reminder of Dean.

"Welcome, Castiel," it said. "Thanks for coming." His eyes morphed into an ugly mottled yellow. Cas bowed his head, his grace humming. He felt his true form begging to be let loose, but he only allowed for the raven-black wings on his back to burn with fiery white light. The two lesser demons evaporated, but the Prince of Hell just watched in amusement.

They launched into action at the exact same moment, Cas leaping forward wielding his angel blade, and the Prince rushing forwards with his fists. Instantly, they got a feel for the other's power. The angel sidestepped the attack, but one blow caught him in the eye. In close proximity, Cas managed to stab the demon in the thigh.

Both hadn't broken a sweat. They didn't speak as they circled one another. And again, they flew at each other. The demon started using the arrow, more like a spear, to block Cas' silver blade. They dueled, sparks literally flying from their weapons. One set of yellow eyes, one of oceanic blue, set on destroying the other.

Cas saw an opening at leapt onto the Prince, crashing through the window out into the snow. The demon smiled and disappeared further out onto the snowy mountain. Cas followed in a flash. Their new battle grounds were eerily similar to the dream Cas had, but he wasn't concentrated on that.

The fighting had picked up speed. It was a dance, and one wrong move meant certain death. They moved further out into the open, teeth bared, both covered in minor wounds and scratches. Then out of nowhere, Cas frozen for a fraction of a second.

 _We're here Cas. You okay?_

The Prince of Hell popped out of the way, loaded the huge arrow, smiled and released the string on the bow. It all happened so quickly, Cas couldn't move. He was stuck in place as the arrow hit its mark in the center of his chest. Immediately, his grace began to shriek and his eyes rolled back with the pain.

He couldn't think straight. The arrowhead. Something wasn't right. Then there was someone holding his mouth, forcing him to look at the demon. Its sulfuric yellow eyes sparkled in glee. "Ah, don't worry. This has just been a taste of the fun we have in store for you."

Cas felt the tickle of cold snow falling on his hair and settling on his limp body. He couldn't even move his eyes, they were glazing over, focusing on the stars. He remembered that night, where he had watched over Sam and Dean as they slept under the night sky in the Impala.

The view was ruined by a pair of luminescent purple irises. "Good work, angel," it spat, pressing its foot on Cas' wound. Then as the world began to spin out of control and Cas' eyesight finally began to get fuzzy, he heard something familiar: a loud rumbling noise. It made his head ache. He felt more pain as someone began to drag him. Laughter echoed around him as he finally blacked out.

 **Uh oh! Sorry Cas, but this is going to get a tad worse. Thanks for reading :)**


End file.
